package com.tyl.forkjoin;

import java.util.concurrent.RecursiveTask;

/*
*求和计算
* 如何使用ForkJoin
* 1、ForkJoinPool通过他来执行
* 2、计算任务ForkJoinPool.execute(ForkJoinTask taslk)
* 3、计算类要继承ForkJoinTask
* */
public class ForkJoinDemo extends RecursiveTask<Long> {

    private Long start;
    private Long end;
    private Long temp=10000L;//临界值

    public ForkJoinDemo(Long start, Long end) {
        this.start = start;
        this.end = end;
    }

    @Override
    protected Long compute() {
        if((end-start)<temp)
        {
            Long sum=0L;
            for (Long i = start; i <end ; i++) {
                sum+=i;
            }
            return sum;
        }else{
            long middle=(start+end)/2;
            ForkJoinDemo task1 = new ForkJoinDemo(start,middle);
            task1.fork();
            ForkJoinDemo task2 = new ForkJoinDemo(middle+1,end);
            task2.fork();
            return task1.join() + task2.join();
        }
    }

}
